Connection of mould parts

ABSTRACT

Disclosed is a method, a mould system and a mould part for a mould system, for manufacture of a component for a wind turbine blade. The mould part may have a moulding surface with a primary side section, a secondary side section, and a central portion between the primary side section and the secondary side section. The mould part has a primary connection interface configured to abut a secondary connection interface of a second mould part. The primary connection interface comprises a primary connection surface substantially perpendicular to the moulding surface. The primary connection interface comprising an outlet configured to be connected to a vacuum source.

FIELD OF THE INVENTION

The present disclosure relates to connection of mould parts of a mouldto form a mould for moulding of a component for a wind turbine blade,such as a shell part or a shear-web, such as an I-web or a C-web, inparticular a mould for vacuum assisted resin transfer.

BACKGROUND

A wind turbine blade is typically assembled by a number of components.For example, a typical wind turbine blade is manufactured by mouldingindividual shell halves, shear webs etc.

A wind turbine blade is typically strengthened by adding shear-webs onthe inside of the wind turbine blade along the length of the windturbine blade. The shear-webs may e.g. be formed in the shape of anI-beam, i.e. an I-web or in the shape of a C, i.e. a C-web.

The shear web may be almost as long as the wind turbine blade. Thus, themould for moulding the shear-web may exceed 70 meters in length. Themould may be sectionised, in particular in the longitudinal or spanwisedirection of the mould. The sectionised mould may be assembled such thatthe shear web may be manufactured as a unitary structure.

In using a vacuum assisted resin transfer moulding method, the mouldshould preferably be air tight. Hence, in using a sectionised mouldinterfaces between sections may be potential sources for formation ofleaks.

SUMMARY

It is an object of the present disclosure to provide methods and devicesfor eliminating or at least reducing the formation of leaks in using asectionised mould for the moulding of components for a wind turbineblade, such as shear-webs or shell parts, in particular in using vacuumassisted resin transfer moulding (VARTM).

Thus, the present invention relates to a mould part, such as a firstmould part, for a mould system, such as a mould system for manufactureof a component for a wind turbine blade.

The mould part has a moulding surface with a primary side section asecondary side section, and a central portion between the primary sidesection and the secondary side section.

The mould part has a primary connection interface configured to abut asecondary connection interface of a second mould part. The mould partmay have a secondary connection interface configured to abut a primaryconnection interface of a tertiary mould part.

The primary connection interface comprises a primary connection surface,e.g. substantially perpendicular to the moulding surface. The secondaryconnection interface may comprise a secondary connection surface, e.g.substantially perpendicular to the moulding surface. The secondaryconnection surface may be opposite the primary connection surface.

The primary connection interface comprises an outlet configured to beconnected to a vacuum source, such as a vacuum source of a mould system.

Also disclosed is a mould system, such as a mould system for manufactureof a component for a wind turbine blade. The mould system comprises afirst mould part, such as the mould part as disclosed, and a secondmould part, such as the mould part as disclosed.

The first mould part has a first moulding surface with a first primaryside section a first secondary side section and a first central portionbetween the first primary side section and the first secondary sidesection.

The first mould part has a first primary connection interface comprisinga first primary connection surface, e.g. substantially perpendicular tothe first moulding surface. The first primary connection interfacecomprises a first outlet configured to be connected to a vacuum source,such as a vacuum source of the mould system. The first mould part mayhave a first secondary connection interface comprising a first secondaryconnection surface, e.g. substantially perpendicular to the firstmoulding surface. The first secondary connection surface may be oppositethe first primary connection surface.

The second mould part has a second moulding surface with a secondprimary side section a second secondary side section and a secondcentral portion between the second primary side section and the secondsecondary side section.

The second mould part has a second secondary connection interfacecomprising a second secondary connection surface, e.g. substantiallyperpendicular to the second moulding surface. The second mould part mayhave a second primary connection interface comprising a second primaryconnection surface, e.g. substantially perpendicular to the secondmoulding surface. The second primary connection surface may be oppositethe second secondary connection surface. The second primary connectioninterface may comprise a second outlet configured to be connected to avacuum source, such as the vacuum source of the mould system.

The first primary connection interface is configured to abut the secondsecondary connection interface. The first secondary connection interfacemay be configured to abut a third primary connection interface of athird mould part. The second primary connection interface may beconfigured to abut a fourth secondary connection interface of a fourthmould part.

Also disclosed is a method for assembling a mould system, such as amould system for manufacture of a component for a wind turbine blade,such as the disclosed mould system. Wherein the mould system comprises afirst mould part and a second mould part.

The method comprises: positioning the first mould part and the secondmould part such that the first primary connection interface abuts thesecond secondary connection interface and applying a first negativepressure to the first outlet by the vacuum source, such as a vacuumsource of the mould system, such as to create a negative pressurebetween the first primary connection interface and the second secondaryconnection interface.

Also disclosed is a method for manufacture of a component for a windturbine blade. The method comprises: positioning a first mould part anda second mould part such that a first primary connection interface ofthe first mould part abuts a second secondary connection interface ofthe second mould part; applying a first negative pressure between thefirst primary connection interface and the second secondary connectioninterface; and applying a second negative pressure between a sealinglayer and the first moulding surface and the second moulding surface.The first negative pressure may be lower than the second negativepressure.

In connecting a plurality of mould parts to form a complete mould ormould system, there is an increased risk that the complete mould surfacemay not be completely air-tight. In particular, the interfaces betweenmould parts provides areas of increased risk of leakage. The presentdisclosure provides a way of connecting the mould parts by applying alow pressure or vacuum in the interface between connecting mould parts.

It is an advantage of the disclosure, that a tighter, e.g. moreair-tight, connection between mould parts may be achieved.

Furthermore, the disclosure provides the advantage that in case ofleaks, air entering the moulding process may be reduced and/orprevented. Thereby, the resulting component may be of a higher quality,and rate of defective components from the manufacturing process may belowered.

The component may be a shear web or the component may be a shell part.The mould system and/or mould part(s) may be for manufacture of a shearweb for a wind turbine blade. Alternatively, the mould system and/ormould part(s) may be for manufacture of a shell part, such as a halfshell, for a wind turbine blade.

The mould system and/or the mould part(s) may be used for vacuumassisted resin transfer moulding (VARTM) of the component, such as byapplying a second negative pressure between a sealing layer and amoulding surface, such as the first moulding surface and/or the secondmoulding surface. The first negative pressure may be lower than thesecond negative pressure. For example, the first negative pressure maybe set to a lower negative pressure than the second negative pressure.By providing a lower pressure in the interface between mould parts, incase of any leaks, resin is drawn from the moulding process and into theinterface rather than air being sucked from the interface an into themoulding process. The first negative pressure may be a predeterminedfraction of the second negative pressure. For example, the firstnegative pressure may be adapted to be the predetermined fraction of thesecond negative pressure. The predetermined fraction may be between0.1-90 percent, such as between 20-80 percent, such as between 50-75percent. The second negative pressure may be between 10-500 mbar, suchas between 10-300 mbar, such as between 100-300 mbar or such as between10-50 mbar. The first negative pressure may be between 0.1-200 mbar,such as between 0.1-100 mbar, such as between 0.1-50 mbar. Thedifference between the first negative pressure and the second negativepressure may be more than 1 mbar, such as more than 10 mbar, such asmore than 50 mbar.

It will be understood that any features explained in relation to oneaspect of the disclosure is applicable also to any other aspect of thedisclosure. For example, it will be understood that any of the featuresas explained in relation to any mould part may apply to a mould part,such as the first mould part and/or the second mould part, of thedisclosed method or mould system.

The central portion may be substantially flat, such as for moulding of ashear web. Alternatively, the central portion may be arc-shaped, such asfor moulding of a shell part, such as a half-shell.

The side sections, such as the primary side section and/or the secondaryside section may comprise a base portion and/or a ramp portion. Forexample, the primary side section may comprise a primary base portionand/or a primary ramp portion. Alternatively, or additionally thesecondary side section may comprise a secondary base portion and/or asecondary ramp portion. The side sections may be configured for adheringthe sealing layer to allow application of the second negative pressurebetween the sealing layer and the moulding surface, such as the firstmoulding surface and/or the second moulding surface. The sealing layermay be adhered to the side section by use of double sided tape, such assealant tape.

The base portion(s), such as the primary base portion and/or thesecondary base portion, may be substantially parallel to the centralportion. The base portion(s) may be positioned at a lower (vertical)level than the central portion. The ramp portion(s), such as the primaryramp portion and/or the secondary ramp portion, may join the centralportion and/or the base portion. The ramp portion(s), such as theprimary ramp portion and/or the secondary ramp portion, may benon-parallel, such as substantially perpendicular, to the centralportion.

The outlet may extend through the primary connection surface. Therebythe vacuum source may be attached, for example, to the outlet frombehind the primary connection surface, to allow for pressurisation ofthe cavity formed between the primary connection surface of the firstconnection interface of the first mould part and the secondaryconnection surface of the secondary connection interface of the secondmould part.

The primary connection interface and/or the secondary connectioninterface may comprise a sealing path. The sealing path may surround theoutlet. Thereby, attaching a vacuum source to the outlet, the pressurein the cavity formed by the primary connection surface of the firstconnection interface of the first mould part and the secondaryconnection surface of the secondary connection interface of the secondmould part may be more effectively lowered.

The sealing path may comprise a plurality of sealing parts, e.g.including a first sealing part, a second sealing part, a third sealingpart and/or a fourth sealing part. For example, the sealing path maycomprise a first sealing part, a second sealing part, a third sealingpart and/or a fourth sealing part.

A sealing part of the sealing path, such as the first sealing partand/or the fourth sealing part may be substantially parallel to thecentral portion. The first sealing part may be extending from theprimary side section to the secondary side section, such as from theprimary ramp portion to the secondary ramp portion. The fourth sealingpart may be extending from the primary side section to the secondaryside section, such as from a primary (e.g. left) outer perimeter of theprimary connection surface to a secondary (e.g. right) outer perimeterof the primary connection surface.

The sealing path and/or a sealing part of the sealing path, such as thefirst sealing part and/or the fourth sealing part, may comprise a recessfor receiving a gasket material, such as an elastic gasket material,such as a rubber gasket material. The gasket material may be removablefrom the recess. For example, the gasket material may be removed toallow for cleaning and/or for replacing.

The first sealing part may be offset from the central portion by adistance, such as a distance of more than 1 mm, such as a distancebetween 1-50 mm, such as between 5-40 mm, such as between 10-25 mm.

The fourth sealing part may be offset from a bottom perimeter of theprimary connection surface by a distance, such as a distance of morethan 1 mm, such as a distance between 1-50 mm, such as between 5-40 mm,such as between 10-25 mm.

The sealing path and/or a sealing part of the sealing path, such as thesecond sealing part and/or the third sealing part, may be configured forreceiving a sealant paste. For example, the sealing path and/or thesealing part of the sealing path, such as the second sealing part and/orthe third sealing part, may be formed by a bevelled edge, such as abevelled edge configured to receive a sealant paste. The sealing part ofthe sealing path, such as the second sealing part and/or the thirdsealing part may be formed, e.g. by a bevelled edge, such as a bevellededge configured to receive a sealant paste, between the moulding surfaceand the primary connection surface, such as between the primary sidesection and the primary connection surface and/or between the secondaryside section and the primary connection surface. For example, the secondsealing part may be between the primary side section and the primaryconnection surface, and/or the third sealing part may be between thesecondary side section and the primary connection surface. Utilizationof a sealing path and/or a sealing part of the sealing path configuredfor receiving a sealant paste, such as a bevelled edge, may beparticularly advantageous for surfaces whereon it is intended to adherethe sealing layer for application of the second negative pressurebetween the sealing layer and the moulding surface, such as the firstmoulding surface and/or the second moulding surface. For example, thesealant paste received in such sealing path or sealing part of suchsealing path, such as in the second sealing part and/or the thirdsealing part, may be configured to be coupled to the sealant tapeadhering to the sealing layer. Thereby the connection of the mould partsreduce the risk of leakage around the interface between the sealinglayer and the interface between mould parts.

The method may comprise applying a sealant paste to a sealing part ofthe sealing path configured for receiving a sealant paste, such as thesecond sealing part and/or the third sealing part.

The primary connection interface may comprise one or more bolts and/orbolt holes, e.g. extending through the primary connection surface. Thebolts and/or bolt holes may provide for a fastening of the primaryconnection interface to the secondary connection interface of the secondmould part. The secondary connection interface may comprise one or morebolts and/or bolt holes, such as to facilitate fastening to a primaryconnection interface of a third mould.

The one or more bolts and/or bolt holes may be surrounded by one or morefifth sealing parts. Thereby, leaks caused by the bolts and/or boltholes may be reduced, facilitating a more effective pressurisation ofthe cavity formed between the primary connection surface and thesecondary connection surface of the secondary connection interface ofthe second mould part.

BRIEF DESCRIPTION OF THE FIGURES

Embodiments of the disclosure will be described in more detail in thefollowing with regard to the accompanying figures. The figures show oneway of implementing the present invention and are not to be construed asbeing limiting to other possible embodiments falling within the scope ofthe attached claim set.

FIG. 1 is a schematic diagram illustrating an exemplary wind turbine,

FIG. 2 is a schematic diagram illustrating an exemplary wind turbineblade,

FIG. 3 is a schematic diagram illustrating a cross-section of anexemplary wind turbine blade,

FIG. 4 is a schematic diagram illustrating an exemplary mould part,

FIG. 5 is a schematic diagram illustrating an exemplary mould system,

FIG. 6 is a schematic diagram illustrating an exemplary connectioninterface,

FIG. 7 is a schematic diagram illustrating exemplary connectioninterfaces,

FIG. 8 is a flow chart of an exemplary method.

DETAILED DESCRIPTION

FIG. 1 illustrates a conventional modern upwind wind turbine 2 accordingto the so-called “Danish concept” with a tower 4, a nacelle 6 and arotor with a substantially horizontal rotor shaft. The rotor includes ahub 8, and three blades 10 extending radially from the hub 8, eachhaving a blade root 16 nearest the hub and a blade tip 14 furthest fromthe hub 8.

FIG. 2 shows a schematic diagram illustrating a wind turbine blade 10.The wind turbine blade 10 has the shape of a conventional wind turbineblade and comprises a root region 30 closest to the hub, a profiled oran airfoil region 34 farthest away from the hub and a transition region32 between the root region 30 and the airfoil region 34. The blade 10comprises a leading edge 18 facing the direction of rotation of theblade 10, when the blade is mounted on the hub, and a trailing edge 20facing the opposite direction of the leading edge 18.

The airfoil region 34 (also called the profiled region) has an ideal oralmost ideal blade shape with respect to generating lift, whereas theroot region 30 due to structural considerations has a substantiallycircular or elliptical cross-section, which for instance makes it easierand safer to mount the blade 10 to the hub. The diameter (or the chord)of the root region 30 may be constant along the entire root area 30. Thetransition region 32 has a transitional profile gradually changing fromthe circular or elliptical shape of the root region 30 to the airfoilprofile of the airfoil region 34. The chord length of the transitionregion 32 typically increases with increasing distance r from the hub.The airfoil region 34 has an airfoil profile with a chord extendingbetween the leading edge 18 and the trailing edge 20 of the blade 10.The width of the chord decreases with increasing distance r from thehub.

A shoulder 40 of the blade 10 is defined as the position, where theblade 10 has its largest chord length. The shoulder 40 is typicallyprovided at the boundary between the transition region 32 and theairfoil region 34.

It should be noted that the chords of different sections of the bladenormally do not lie in a common plane, since the blade may be twistedand/or curved (i.e. pre-bent), thus providing the chord plane with acorrespondingly twisted and/or curved course, this being most often thecase in order to compensate for the local velocity of the blade beingdependent on the radius from the hub.

The blade is typically made from a pressure side shell part 36 and asuction side shell part 38 that are glued to each other along bond linesat the leading edge 18 and the trailing edge of the blade 20.

FIG. 3 shows a schematic diagram illustrating a cross section of theblade along the line I-I shown in FIG. 2. As previously mentioned, theblade 10 may comprise a pressure side shell part 36 and a suction sideshell part 38. The pressure side shell part 36 comprises a spar cap 41,also called a main laminate, which constitutes a load bearing part ofthe pressure side shell part 36. The spar cap 41 comprises a pluralityof fibre layers 42 mainly comprising unidirectional fibres aligned alongthe longitudinal direction of the blade in order to provide stiffness tothe blade. The suction side shell part 38 also comprises a spar cap 45comprising a plurality of fibre layers 46. The pressure side shell part38 may also comprise a sandwich core material 43 typically made ofbalsawood or foamed polymer and sandwiched between a number offibre-reinforced skin layers. The sandwich core material 43 is used toprovide stiffness to the shell in order to ensure that the shellsubstantially maintains its aerodynamic profile during rotation of theblade. Similarly, the suction side shell part 38 may also comprise asandwich core material 47.

The spar cap 41 of the pressure side shell part 36 and the spar cap 45of the suction side shell part 38 are connected via a first shear web 50and a second shear web 55. The shear webs 50, 55 are in the shownembodiment shaped as substantially I-shaped webs. The first shear web 50comprises a shear web body and two web foot flanges. The shear web bodycomprises a sandwich core material 51, such as balsawood or foamedpolymer, covered by a number of skin layers 52 made of a number of fibrelayers. The second shear web 55 has a similar design with a shear webbody and two web foot flanges, the shear web body comprising a sandwichcore material 56 covered by a number of skin layers 57 made of a numberof fibre layers.

The sandwich core material 51, 56 of the two shear webs 50, 55 may bechamfered near the flanges in order to transfer loads from the webs 50,55 to the main laminates 41, 45 without the risk of failure andfractures in the joints between the shear web body and web foot flange.However, such a design will normally lead to resin rich areas in thejoint areas between the legs and the flanges. Further, such resin richarea may comprise burned resin due to high exothermic peeks during thecuring process of the resin, which in turn may lead to mechanical weakpoints. In order to compensate for this, a number of filler ropes 60comprising glass fibres are normally arranged at these joint areas.Further, such ropes 60 may also facilitate transferring loads from theskin layers of the shear web body to the flanges. However, alternativeconstructional designs are possible.

The blade shells 36, 38 may comprise further fibre-reinforcement at theleading edge and the trailing edge. Typically, the shell parts 36, 38are bonded to each other via glue flanges in which additional fillerropes may be used (not shown). Additionally, very long blades maycomprise sectional parts with additional spar caps, which are connectedvia one or more additional shear webs.

A shear web may extend throughout the majority of the length of the windturbine blade. Thus, the shear web may exceed 70 meters in length.Consequently, the shear web mould needed to manufacture the shear websmay need to be more than 70 meters in length. To facilitatetransportation and/or storage of such a shear web mould, it may bedivided into several parts, i.e. mould parts, of approximately 10-12metres in length, that are assembled together to form a completee.g. >70-meter-long, shear web mould or mould system.

FIGS. 4-7 shows examples of mould parts and mould systems beingconfigured for manufacture of a shear web for a wind turbine blade.However, it will be understood that the described concepts may besimilarly applied to a mould system and/or mould parts being shaped formoulding other components of a wind turbine blade, such as a blade shellmould.

FIG. 4 is a schematic diagram illustrating an exemplary mould part 100,such as a shear web mould part. The mould part 100 may be a first mouldpart and/or a second mould part of a mould system, such as a shear webmould system for manufacture of a shear web for a wind turbine blade.

The mould part 100 has a moulding surface 102. The moulding surface 102is facing substantially upwards, such as to provide a surface for layingout components, such as glass-fibre for the shear web.

The moulding surface 102 comprises a primary side section 104, asecondary side section 106 and a central portion 108. The centralportion 108 is between the primary side section 104 and the secondaryside section 106. The central portion 108 is substantially flat.However, if the mould part 100 was supposed to be used for moulding ofanother component of the wind turbine blade, the central portion 108 mayhave been formed differently, e.g. the central portion may be curved,e.g. having a half-circular cross section.

The primary side section 104 comprises a primary base portion 118 and aprimary ramp portion 120. The primary base portion 118 is substantiallyparallel to the central portion 108. The primary ramp 120 portion joinsthe central portion 108 and the primary base portion 118. The primaryramp portion 120 is non-parallel to the central portion 108. The primarybase portion 118 and the central portion 108 are levelled differentlyand the primary ramp portion 120 joins the central portion 108 and theprimary base portion 118. The primary ramp portion 120 may besubstantially vertical.

The secondary side section 106 comprises a secondary base portion 122and a secondary ramp portion 124. The secondary base portion 122 issubstantially parallel to the central portion 108. The secondary ramp124 portion joins the central portion 108 and the secondary base portion122. The secondary ramp portion 124 is non-parallel to the centralportion 108. The secondary base portion 122 and the central portion 108are levelled differently and the secondary ramp portion 124 joins thecentral portion 108 and the secondary base portion 122. The secondaryramp portion 124 may be substantially vertical.

The mould part 100 has a primary connection interface 110 and asecondary connection interface 112. The secondary connection interface112 is opposite the primary connection interface 110. The connectioninterfaces 110, 112 are configured to abut corresponding connectioninterfaces of other mould parts of a mould system. For example, theprimary connection interface 110 is configured to abut a secondaryconnection interface 112′ of a second mould part 100′ (see FIG. 5).

For some mould parts, such as mould parts configured to form ends of amould system, either the primary connection interface 110 or thesecondary connection interface 112 may be omitted or be substituted withan end section.

The primary connection interface 110 comprises a primary connectionsurface 114. The primary connection surface 114 is substantiallyperpendicular to the moulding surface 102. The primary connectionsurface 114 is substantially perpendicular to a longitudinal directionof the mould part 100 and/or the mould system.

The primary connection interface 110 comprises an outlet 116. The outlet116 extends through the primary connection surface 114. The outlet 116is configured to be connected to a vacuum source, such as a compressor.By connecting the outlet 116 to a vacuum source, a low pressure may beapplied between the mould parts. Thereby, the mould parts may be heldtogether, and a tighter seal between the mould parts may be achieved,facilitating moulding of a higher quality shear web, and providing for asimpler and faster manufacturing process.

The primary connection interface 110 comprises a sealing path 130. Thesealing path 130 may provide for adding a sealant, such as to providefor an air-tight (or near air-tight) seal between the primary connectionsurface 114 and a secondary connection surface of the second mould part.The sealing path 130 is surrounding the outlet 116. For example, thesealing path 130 is substantially following the perimeter of the primaryconnection surface 114. The sealing path 130 comprises a first sealingpart 132. The sealing path 130 is described in more detail below, e.g.in relation to FIG. 6.

The primary connection interface 110 comprises one or more bolts and/orbolt holes 126. The bolts and/or bolt hoes may extend through theprimary connection surface 114. The secondary connection interface 112comprises corresponding bolts and/or bolt holes, which may extendthrough the secondary connection surface 115. Thus, the bolts and/orbolt holes are provided to attach a primary connection interface 110 ofa first mould part to a secondary connection interface of a second mouldpart.

FIG. 5 is a schematic diagram illustrating an exemplary mould system200, such as a shear web mould system for manufacture of a shear web fora wind turbine blade. The mould system 200 comprises a first mould part100 and a second mould part 100′. Although not illustrated, the mouldsystem 200 may comprise more than two mould parts, such as three, four,five, six, seven, eight or more mould parts.

The first mould part 100 is described in more detail in relation to FIG.4. The second mould part 100′ may be similar to the first mould part 100as described in more detail in relation to FIG. 4.

As seen, the primary connection interface 110 of the first mould part100 is abutting and connection to the secondary connection interface112′ of the second mould part 100′.

A third mould part (not shown) may be connected to the first mould part100 by connecting to the secondary connection interface 112 of the firstmould part 100.

A fourth mould part (not shown) may be connected to the second mouldpart 100′ by connecting to the primary connection interface 110′ of thesecond mould part 100′.

FIG. 6 is a schematic diagram illustrating an exemplary connectioninterface,

The primary connection interface 110 comprises a sealing path 130. Thesealing path 130 is surrounding the outlet 116. For example, the sealingpath 130 is substantially following the perimeter of the primaryconnection surface 114.

The sealing path 130 comprises a first sealing part 132. The firstsealing part 132 comprises a recess for receiving a gasket material. Thefirst sealing part 132 is substantially parallel to the central portion108. The first sealing part is extending from the primary side section104 to the secondary side section 106, such as from the primary rampportion 120 to the secondary ramp portion 124. The first sealing part132 is offset from the central portion 108, e.g. by a distance between1-50 mm. The offset may provide for a better seal, in particular whenusing a gasket material.

The sealing path 130 comprises a second sealing part 134. The secondsealing part 134 is formed by a bevelled edge between the mouldingsurface and the primary connection surface 114, such as between theprimary side section 104 and the primary connection surface 114, asshown. The second sealing part 134, e.g. by the bevelled edge, isconfigured for receiving a sealant paste.

The sealing path 130 comprises a third sealing part 136. The thirdsealing part 136 is formed by a bevelled edge between the mouldingsurface and the primary connection surface 114, such as between thesecondary side section 106 and the primary connection surface 114, asshown. The third sealing part 136, e.g. by the bevelled edge, isconfigured for receiving a sealant paste.

The sealing path 130 comprises a fourth sealing part 138. The fourthsealing part 138 comprises a recess for receiving a gasket material. Thefourth sealing part 138 is substantially parallel to the central portion108. The fourth sealing part 138 is extending from the primary sidesection 104 to the secondary side section 106. The fourth sealing part138 is offset from a bottom perimeter of the primary connection surface114, e.g. by a distance between 1-50 mm. The offset may provide for abetter seal, in particular when using a gasket material.

The primary connection interface comprises fifth sealing part(s) 140.The fifth sealing part(s) 140 is surrounding the bolt and/or bolt holes126. The fifth sealing part(s) may prevent leakage through the boltholes.

FIGS. 7a and 7b are schematic diagrams illustrating exemplary connectioninterfaces.

FIG. 7a is a cross-sectional view of the primary connection interface110 of FIG. 6, along line A-A. As shown, the second sealing part 134 isformed by a bevelled edge between the primary side section, such as theprimary base portion 118, and the primary connection surface 114. Also,as shown, the fourth sealing part 138 comprises a recess for receiving agasket material. It is further illustrated that the fourth sealing part138 is offset from a bottom perimeter of the primary connection surface114.

FIG. 7b shows the primary connection interface 110 of FIG. 7a , such asof a first mould part 100, being connected to a secondary connectioninterface 112′ of a second mould part 100′.

A gasket material 142 is applied in the recess formed by the fourthsealing part 138. As illustrated, a secondary connection interface, suchas the secondary connection interface 112′ of the second mould part 100′need not have a sealing part to receive the gasket material 142.However, in other exemplary mould parts the secondary connectioninterface may be provided with a sealing part to receive a gasketmaterial.

A sealant paste 144 is applied in the recess formed by the bevelled edgeof the second sealing part 134. As illustrated a secondary connectioninterface, such as the secondary connection interface 112′ of the secondmould part 100′ may be provided with a bevelled edge to receive thesealing paste 144. In other exemplary mould parts, the secondaryconnection interface may be provided without the bevelled edge. In otherexemplary mould parts, the primary connection interface may be providedwithout the bevelled edge. Hence, it will be understood that thebevelled edge may be provided in either one or both of the connectioninterfaces to form the recess for receiving the sealant paste 144.

FIG. 8 is a flow chart of an exemplary method 300, such as a method forassembling a mould system for manufacture of component, such as a shearweb or a shell part, for a wind turbine blade, such as the mould system200 as described above comprising a first mould part 100 and a secondmould part 100′.

The method 300 comprises positioning 302 the first mould part and thesecond mould part such that a primary connection interface of the firstmould part, e.g. a first primary connection interface, abuts a secondaryconnection interface of the second mould part, e.g. a second secondaryconnection interface.

The method further comprises applying 303 a sealant paste to a sealingpart of the sealing path forming a bevelled edge between the firstmoulding surface and the first primary connection surface and/or betweenthe second moulding surface and the second secondary connection surface.For example, the sealant paste may be applied 303 to the second sealingpart and/or the third sealing part of the sealing path as describedabove.

The method further comprises applying 304 a first negative pressure toan outlet of the first mould part, e.g. a first outlet, by a vacuumsource.

The mould system may be used for vacuum assisted resin transfer moulding(VARTM) of the component, e.g. by applying a second negative pressurebetween a sealing layer and the moulding surfaces of the mould parts,such as a first moulding surface of the first mould part and a secondmoulding surface of the second mould part.

The first negative pressure applied 304 to the outlet may be lower thanthe second negative pressure used in the VARTM process. Thereby it maybe ensured that if there is a leak in the interfaces between mouldparts, resin is entering the interface rather than air entering into themoulding process.

The invention has been described with reference to a preferredembodiment. However, the scope of the invention is not limited to theillustrated embodiment, and alterations and modifications can be carriedout without deviating from the scope of the invention.

LIST OF REFERENCES

-   2 wind turbine-   4 tower-   6 nacelle-   8 hub-   10 blade-   14 blade tip-   16 blade root-   18 leading edge-   20 trailing edge-   30 root region-   32 transition region-   34 airfoil region-   36 pressure side shell-   38 suction side shell-   40 shoulder-   41 spar cap-   42 fibre layers-   43 sandwich core material-   45 spar cap-   46 fibre layers-   47 sandwich core material-   50 first shear web-   51 sandwich core material-   52 skin layers-   55 second shear web-   51 sandwich core material-   52 skin layers-   55 second sear web-   56 sandwich core material-   57 skin layers-   60 filler ropes-   100 shear web mould part-   102 moulding surface-   104 primary side section-   106 secondary side section-   108 central portion-   110 primary connection interface-   112 secondary connection interface-   114 primary connection surface-   115 secondary connection surface-   116 outlet-   118 primary base portion-   120 primary ramp portion-   122 secondary base portion-   124 secondary ramp portion-   126 bolt(s)-   128 bolt hole(s)-   130 sealing path-   132 sealing part-   134 second sealing part-   136 third sealing part-   138 fourth sealing part-   140 fifth sealing part(s)-   142 gasket material-   144 sealing paste-   146 primary mould insert-   148 secondary mould insert-   200 shear web mould system-   300 method-   302 positioning first mould part and second mould part-   303 applying sealant paste-   304 applying first negative pressure

1-11. (canceled)
 12. Method for assembling a mould system formanufacture of a component for a wind turbine blade, the mould systemcomprising: a first mould part having a first moulding surface with afirst primary side section a first secondary side section and a firstcentral portion between the first primary side section and the firstsecondary side section, the first mould part having a first primaryconnection interface comprising a first primary connection surface, thefirst primary connection interface comprising a first outlet configuredto be connected to a vacuum source, a second mould part having a secondmoulding surface with a second primary side section a second secondaryside section and a second central portion between the second primaryside section and the second secondary side section, the second mouldpart having a second secondary connection interface comprising a secondsecondary connection surface, the first primary connection interfaceand/or the second secondary connection interface comprising a sealingpath configured for surrounding the outlet, and wherein the sealing pathcomprises a sealing part formed by a bevelled edge between the firstmoulding surface and the first primary connection surface and/or betweenthe second moulding surface and the second secondary connection surface,the method comprising: positioning the first mould part and the secondmould part such that the first primary connection interface abuts thesecond secondary connection interface, applying a sealant paste to thesealing part of the sealing path, applying a first negative pressure tothe first outlet by the vacuum source.
 13. Method according to claim 12,wherein the mould system is used for vacuum assisted resin transfermoulding (VARTM) of the component by applying a second negative pressurebetween a sealing layer and the first moulding surface and the secondmoulding surface, and wherein the first negative pressure is lower thanthe second negative pressure.
 14. Method for manufacture of a componentfor a wind turbine blade comprising: positioning a first mould part anda second mould part such that a first primary connection interface ofthe first mould part abuts a second secondary connection interface ofthe second mould part; applying a first negative pressure between thefirst primary connection interface and the second secondary connectioninterface; applying a second negative pressure between a sealing layerand the first moulding surface and the second moulding surface, andwherein the first negative pressure is lower than the second negativepressure.
 15. Method according to claim 14, wherein the first negativepressure is a predetermined fraction of the second negative pressure.16. Method according to claim 15, wherein the predetermined fraction isbetween 10-70 percent.
 17. Method according to claim 14, wherein thesecond negative pressure is between 10-500 mbar.
 18. Method according toclaim 14, wherein the first negative pressure is between 0.1-200 mbar.